Support for a seal for floating roofs



Jan. 16, 1951 F. 1 GoLDsBY ETAL SUPPORT FOR A SEAL FOR FLOATING ROOFS 2Sheets-Sheet l Filed Dec. 22, 1945 x/ w ad.,

i MLM Jan. 16, 1951 F. 1 GoLDsBY ET A1.

SUPPORT FOR A SEAL FOR FLOATING ROOFS 2 Sheets-Sheet 2 Filed D60. 22,1945 l HI) gym n g fig??- rmnied ne. 1e, 1951 2,537,987 SUPPORT FOR ASEAL FOB I'LOATING BOOFS Fred L. Goldlby and Cliord M. n', Chicago,lll.,

aseignora to Chicago Bridge Iron Company, a corporation of IllinoisApplication December 22, 1945, Serial No. 837,017

3 Claims.

1 This invention relates to a floating roof tank, and particularly to aseal for sealing the area between the iioating roof and the shell of thetank.

Floating rcoi' tanks are generally used for the storage oi' volatileliquids where the roof floats on top of the liquid. There is ordinarilyan annular area between the edge of the floating roof and the shell ofthe tank. In order to avoid evaporation losses and to preventcontamination of the contents of the tank by dirt, rain water, and thelike, it is necessary that a sealing means be provided, sealing o thisarea. Various types of sealing means have been proposed in the past butmany of these have been unsatisfactory because of excess weight, bulk,and the like, and many have been diilicult to install and maintain.

A new type sealing means has been developed that employs a flexiblesealing ring to contact the shell of the tank with hanger means tosupport the ringr in sealing contact with the shell. The new sealingring is so constructed that it readily slides up and down the tankshell, as the roof rises and falls, and is made quite ilexible so as tofollow the contour of the shell if the shell should get out of round.The new hanger means supports the sealing ring in position and providesoutward pressure to hold the ring against the shell at all times. Thehanger means is preferably rotatable so that sideways shifting of thering may be accommodated. There is also preferably provided meanstending to return the hanger means to its original position when thesealing ring has shifted from its normal position.

One of the chief advantages of the new sealing ring is that it providesvery close contact with the shell of the tank, and this contact ismaintained when the ring is supported at spaced points.

The invention will be described as related to the embodiment set out inthe accompanying drawings. Of the drawings Fig. l is a fragmentary planview of a oating roof tank embodying the invention; Fig. 2 is a verticalsection taken along line 2 2 of Fig. l; Fig 3 is a horizontal sectionshowing one curvature arrangement of the sealing.. ring `when there isno outward pressure applied; Fig. 4 is vertical sections taken alongline 4-4 of Fig. 3; Figs. 5 to 8 inclusive illustrate individual stepsof a preferred method of forming flexures in the new sealing ring andFig. 9 is a horizontal section taken along line 9-9 of Fig. 2.

The floating roof tank shown in the accom' Bullying drawings comprises ashell Il and a 2 floating roof il therein. The space between the edge ofthe floating roof and the shell of the tank is provided with a sealingmeans to prevent evaporation and contamination of the storedl liquid.

The sealing means shown comprises an annular sealing ring il contactingthe inner surface oi' the shell III and supported by hanger means Ilmounted around the edge of the iloating roof Il. The annular sealingring I2 is provided with spaced vertical ilexures Il extending betweentop il and bottom i8 marginal areas.' These marginal areas arepreferably bent back from the vertical and away from the shell in ordervto permit the sealing ring to pass over raised sections on the innersurface of the shell.

The fiexures i4 are formed in the sealing ring I2, which is preferablymade of sheet metal, and they extend away from the body portion of thelsealing ring. The flexures have the form oi loops formed in the sheetmetal with inner portions l1 adjacent each other in order to allow forexpansion and contraction of the sealing ring. The flexures may begenerally rounded, as indicated. These iiexures not only permitexpansion and contraction of the ring, but also permit the ring to bendeasily. One method of making the ilexures is shown in Figs. 5 to 8inclusive. In this method a cut-out portion I9 is formed at one edge ofthe ring. A second similar cut-out portion is formed on the oppositeedge of the ring and opposite the first portion. A third cut-out portion20 is formed extending from the inner end of the first portion, and -afourth cut-out portion similar to the third is formed adjacent the otheredge of the ring. The third and fourth cut-out portions have one edge 2|substantially parallel to -its edge of the ring, and have another edge22 of arcuate shape with the arc extending away from its edge of thering. The fourth cut- 'out portion is formed in the same manner. The

ilexure il is formed by bringing the opposite ends of the third andfourth cut-out portions adjacent each other to form a fold. Theoverlapping edges 23 and 24 adjacent the first and second cut-outportions are left free so as to be slidable relative to each other.Thismethod forms a ilexure il having top 25 and bottom 2l edges slopedtoward each other at an acute angle to the main body portion of thering. It is preferred that the top and bottom ends be thusly sloped,although such construction is not absolutely necessary.

Any type oi hanger means desired may be used to support the new sealingring. The hanger means shown comprises a T bar Il extending betweenadjacent exures I4 and attached to the sealing ring I2 by means of shortbrackets 26. The T bar 21 is loosely held by the brackets 28 in order topermit bending of the section 29 of the sealing ring between adjacentiiexures I4. This loose connection may be provided by slots 30 providedin the brackets 28 and engaging studs 3l in the ends of the T bar. Y

The horizontal portion 32 of the T bar 21 extends toward the floatingroof. A substantially horizontal pipe 33 is provided having a yoke end3d with one leg of the yoke above and the other leg below the horizontalportion. A threaded bolt IE5 is loosely held in the yoke 3d and engagesthreads in the horizontal portion 32. The bolt S5 extends above the yoke3ft, and a spring 3E is located between the upper end ci the bolt andthe top surface of the upper yoke leg. There is also provided a secondpipe 3l of larger diameter than the rst pipe 33, and through which thefirst pipe extends. The first pipe 33 is provided with a roller 33 heldin top and bottom slots in the rst pipe 3E and mounted by means of pinfor rolling contact with the inside surface oi' the second pipe 3l. pipe33, opposite the yoke 34, there is located a cap 4I closing this end ofthe pipe. On the corresponding end of the second pipe 31 there islocated an annular cap 42 having a hole 43 therein through which the rstpipe 33 extends. The hole 43 is of such size that the cap 4i on the endof the first pipe will contact the annular cap 42 when the rst pipe hasbeen extended its full `distance toward the shell of the tank. Betweenthe annular cap 42 and the roller 38 there is provided an annular collar44 on the first pipe 33. This collar is of such diameter that it slidesfreely within the second pipe 3l. Between the annular cap 42 and thecollar 44 there is provided a spring 45 normally urging the first pipe33 toward the shell of the tank.

In order to support the second pipe 31 and the iirst pipe 33 there isprovided a third pipe 46, attached near the front end of the second pipe3l and extending downwardly therefrom. rlhis third pipe abuts the 'edgesof a hole 4B in a horizontal base plate 41. The third pipe 46 isrotatably held concentric to the hole 48 by providing a smallerconcentric pipe 49 extending through the hole 48 with the concentricpipe being attached to the third pipe as by welding 50. On the bottom ofthe concentric pipe 49 there are located three lugs 5I in order to holdthe assembly in place. In assembling the structure the lugs 5I may beinserted through cut-out portions 52 at the edge of the hole 48. Thelugs 5I and cut-out portions 52 are arranged so that they wil1 notcoincide when the hanger means is in use.

The base plate 41 is supported on vertical threaded posts 53 mounted onthe deck `of the iloating roof. The base plate is held on the post bymeans of nuts 54'on either side of the base plate so that the positionof the plate may be easily regulated. y

In order to take up some of the load of the sealing ring I2 a spring 55is provided extending substantially vertically from the rear of the baseplate 41 to the second pipe 31. The spring is attached to the base plateby means of a hole 56 at the rear of the plate and is attached to thepipe 31 -by means of a downwardly extending eye 51. Any type sealingmeans may be provided between the sealing ring I2 and the edge of thefloating roof II. As shown, this. sealing means comprises a flexiblesealing member 58 made of fabric im- On the end of the first pregnatedwith a flexible impervious material. The sealing member 58 is attachedto the sealing ring ,by means of bolts 58 extending through a washer bar60 and the sealing ring I2. The roo! edge of the sealing member 531sattached to the rooi' by means of hooks 6I holding wedges l2 pressingagainst a circular rod 83 in contact with the roof edge ci the sealingmember 58. Any other means of fastening may be used if desired.

The sealing ring l2 may also be provided with any type of secondary seal(not shown) for sealing any areas between the shell I0 and the sealingring it.

The spring 38 around the top end of bolt 2l is provided so that each oithe hanger means Il will carry its proportionate share of the load ofthe sealing ring. The bolt 35 serves to adjust the position of the T'bar2 with respect to the first pipe 33 and may be used to even up the loadon all hangers. The spring 46 around the first pipe 33 serves to holdthe sealing ring tightly against the shell it?. The spring 55 betweenthe base plate 4i and the second pipe 31 applies a vertical load to theinner end of the second pipe and serves to at least partially balancethe load of the sealing ring. If the sealing ring should move to oneside of its normal position the spring 55 also applies a force tendingto restore the pipe 3l to a radial position. The spring 55 reduces thebending moment at the base plate 41 and helps to prevent breakage of thehanger. The spring 55 is of such strength that the moment when the roofis moving up is approximately the same but oi opposite sign as themoment when the roof moves down. This is accomplished by providing aspring that would resist a load equal to the weight of the sealing ring.This of course is not essential, and the spring load could be made suchthat the moment at the connection at the base plate 41 would always beof the same sign, but of varying magnitude. The spring, or any similarreinforcement, may be eliminated if desired and the connection at thebase plate be made strong enough to withstand all force to which itwould be subjected.

The base plate 41 is mounted on the threaded posts 53 so that each platecan be levelled and adjusted vertically. For propel` operation it ispreferred that all the hanger means be in a substantially horizontalplane. Since the top of the floating roof may vary somewhat from ahori-i zontal plane the vertical adjustment is required. Since the pipe31 is mounted for rotational movement in a horizontal plane it isnecessary that the base plate be kept approximately level. and thus aminimum of three posts 53 is required.

The sealing ring is preferably constructed so that portions of the ringbetween adjacent ilexures should have radii of curvature, whenunrestrained, diering from the radius of the shell. The hanger meanswill then be arranged to press against the ring at points substantiallyadjacent where the distance between the shell and the ring tends to bethe greatest. By pressing at these points adequate contact may bemaintained over substantially the entire surface of the sealing ring.This principle of construction is shown in Fig. 3, where the radius ofthe portion 23 is less than the radius of the shell and the hanger meanspress against the ends of the portion 23. If desired, however, thesealing ring may be of substantially the same radius of curvature as theradius of the shell. Although the sealing means has been shown with thehanger pressing against the shoe at areas between 'ilexures the hangersmay be constructed to press at the ilexures themselves if desired. Asshown, one hanger means is shown operating between two adjacentilexures. If desired, however, one may be used for each ilexure or forany combination of flexures. It is preferred, however, that at least onehanger be provided for not more than three flexures.

Wherev secondary seals are used these seals may be attached to the topmarginal area of the sealing ring. They may be held on the sealing ringitself, or may be held by upstanding brackets attached to the ring.Joints between individual sections of the sealing ring may be joined inany manner desired. Thus the ends of adjoining sections may be rivetedor bolted together; they may be bent and riveted or bolted;

l or may be joined by flexible sealing members.

These guide means may be any type desired.

One form is to provide a vertical bar attached to the inner surface ofthe shell and to provide a crimped portion in the sealing ring passingaround the bar. The combination of crimped portion and bar will preventany substantial lateral movement of the sealing ring. Such arrangementswill not be necessary on tanks of small diameter.

Having described the invention as related to the embondiments shown inthe accompanying drawings, it is intended that theinvention be notlimited to any of the details of description unless otherwise specified,but rather be construed broadly within its spirit and scope as set out1n the accompanying claims.

We claim:

1. In a floating roof tank or the like a hanger means to be attached tothe floating roof to support a sealing member against the shell of thetank, said hanger means comprising an elongated, substantiallyhorizontal bracket having its ends pivotally attached to the sealingmember i'or pivotal movement in a substantially horizontal plane, theintermediate portion oi' the bracket being spaced from the sealingmember, a horizontal pipe supporting the sealing member` and having ayoke end with the yoke portion having one leg above and the other legbelow said intermediate portion, a threaded bolt loosely held in saidyoke and engaging threads in said intermediate portion, a spring heldbetween the upper end of the bolt and the top surface of the upper yokehis.A a secondy pipe mounted on the noating roof with the rst pipeVextending therethrough, a roller held by the nrst pipe in rollingcontact with the inside of the second pipe. laterally projectingshoulders on the end ofthe vilrst pipe opposite the yoke, an annularclosure on the corresponding end of the second pipe through which thefirst pipe extends, an annular collar on the nrst pipe between theannular closure and the :sol

roller and normally within the second pipe, a spring surrounding the rstpipe and held between the annular closure and the annular collar andnormally urging the first pipe in the direction of its yoke end, andadjustable mounting means for lmounting the second pipe on the floatingroof.

2. In a iioating roof tank having a shoe for slidably contacting theshell of the tank, support means for the shoe comprising an elongatedsubstantially horizontal bracket having its ends pivotally attached tothe shoe for pivotal movement in a substantially horizontal plane, theintermediate portion of the bracket being spaced from the shoe, ahorizontal pipe having a yoke end with the yoke portion having one legabove and the other leg below said intermediate portion, attaching meansfor securing said yoke to said intermediate portion for relativevertical adjustment therebetween, a 'second horizontal pipe mounted onthe floating roof and having the first pipe telescoped thereinto, and aspring held 1 inside said second pipe and operating against the ilrstpipe for urging the first pipe toward the shell of the tank. I

3. A support means comprising a base, asealing member having an arcuateportion and adapted to contact a surface, an elongated substantiallyhorizontal bracket having its ends piv- .otally attached to the sealingmember for pivotal movement in a substantially horizontal plane with theintermediate portion of the bracket forming a chord of said arc, a rstpipe pivotallyl attached to the intermediate portion of the bracket forpivotal movement in a substantially horizontal plane, a second pipemounted on the base and having the first pipe telescoped thereinto andsupporting saidI` first pipe, and means urging the first pipe awayffromthe second pipe in the direction of the sealing member to press thesealing member against the surface in sealing relation.

FRED L. GOLDSBY.

CLIFFORD M. ORR.

REFERENCES CITED The following references are oi record in the ille ofthis patent:

UNITED STATES PATENTS

